Which process merges two haploid gametes to form a diploid cell?

Which process merges two haploid gametes to form a diploid cell?

• A. Fertilization
• B. Mitosis
• C. Meiosis
• D. Cytokinesis

Answer: (A)

Fertilization is the process that merges two haploid gametes to form a diploid cell. Each gamete carries one complete set of chromosomes, so when sperm and egg unite, the resulting zygote has two sets of chromosomes—one from each parent. This restores the diploid chromosome number and kickstarts development, with the zygote then dividing by mitosis as it grows. Mitosis, by contrast, is cell division that preserves the chromosome number, producing two genetically identical diploid cells from a diploid starting cell. It does not involve fusion of gametes. Meiosis reduces the chromosome number, producing haploid gametes for sexual reproduction, not fusing them. Cytokinesis is the physical splitting of the cytoplasm at the end of cell division, completing mitosis or meiosis, but on its own it does not merge gametes.

Fertilization is the process that merges two haploid gametes to form a diploid cell. Each gamete carries one complete set of chromosomes, so when sperm and egg unite, the resulting zygote has two sets of chromosomes—one from each parent. This restores the diploid chromosome number and kickstarts development, with the zygote then dividing by mitosis as it grows.

Mitosis, by contrast, is cell division that preserves the chromosome number, producing two genetically identical diploid cells from a diploid starting cell. It does not involve fusion of gametes.

Meiosis reduces the chromosome number, producing haploid gametes for sexual reproduction, not fusing them. Cytokinesis is the physical splitting of the cytoplasm at the end of cell division, completing mitosis or meiosis, but on its own it does not merge gametes.